1. Field of the Invention
The present invention generally relates to an information recording apparatus and an information reproducing apparatus, and more particularly to an information recording apparatus for recording audio information and video information to a record medium such as an optical disk, and an information reproducing apparatus for reproducing the audio information and video information from the record medium.
2. Description of the Related Art
Audio information and video information are recorded on a record medium such as an optical disk, a video tape and the like.
The information may be recorded on such a record medium in a form of an analog signal or a digital signal. The method of recording the information by means of the digital signal is superior to that by means of the analog signal since the degradation in the sound quality and the image quality of the digital signal is less than that of the analog signal, and the digital signal can be more easily dealt with by the computer.
There is a multiple audio music accompaniment apparatus (hereinafter, it is called as a "karaoke apparatus") as an applied system by use of such a record medium, which records audio information of 4 channels (i.e. two audio main channels and two audio sub channels).
As one type of this karaoke apparatus, there is one which predetermines such a rule that the audio sub channels (i.e. the 3.sup.rd and 4.sup.th channels) are recorded with the model singing (i.e. the guide voice), so that the audio information including the model singing can be used for practice.
Therefore, in this type of karaoke apparatus, since the condition of using each channel is predetermined in advance, it is not necessary to record on the record medium the information describing the condition of using each channel. Thus, such information describing the condition of using each channel is not really recorded on the record medium.
On the other hand, as another type of the karaoke apparatus, there is one which records audio signals independent from each other to the 4 channels, records the accompaniment sound and the model singing corresponding to one of the two singers to the sub channels (3.sup.rd and 4.sup.th channels) respectively in case of the duet karaoke music composition, and records the information as for the condition of using the audio channels for each music composition, on the record medium. In this case, the information recordable for each channel is predetermined in advance.
Since what is recorded to each audio channel (i.e. the channel format) is predetermined in advance in the above explained types of karaoke apparatus, the degree of freedom for recording and reproducing is certainly restricted, which is a problem.
Further, since the channel format is predetermined in advance, the record medium, which can be reproduced by one type of karaoke apparatus employing one type of channel format, cannot be reproduced by another type of karaoke apparatus employing another type of channel format as it is. In order to utilize the music composition on the record medium by this another type of karaoke apparatus, it is necessary to manufacture a new record medium based on this another type of channel format.